Mark device_class type hints as compulsory in sensor platform (#160931)

homeassistant/components/ebusd/sensor.py

@@ -5,7 +5,7 @@ from __future__ import annotations
 import datetime
 import logging
 
-from homeassistant.components.sensor import SensorEntity
+from homeassistant.components.sensor import SensorDeviceClass, SensorEntity
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity_platform import AddEntitiesCallback
 from homeassistant.helpers.typing import ConfigType, DiscoveryInfoType
@@ -96,7 +96,7 @@ class EbusdSensor(SensorEntity):
         return None
 
     @property
-    def device_class(self):
+    def device_class(self) -> SensorDeviceClass | None:
         """Return the class of this device, from component DEVICE_CLASSES."""
         return self._device_class
 

homeassistant/components/mfi/sensor.py

@@ -116,7 +116,7 @@ class MfiSensor(SensorEntity):
         return round(self._port.value, digits)
 
     @property
-    def device_class(self):
+    def device_class(self) -> SensorDeviceClass | None:
         """Return the device class of the sensor."""
         try:
             tag = self._port.tag

homeassistant/components/oasa_telematics/sensor.py

@@ -84,7 +84,7 @@ class OASATelematicsSensor(SensorEntity):
         return self._name
 
     @property
-    def device_class(self):
+    def device_class(self) -> SensorDeviceClass:
         """Return the class of this sensor."""
         return SensorDeviceClass.TIMESTAMP
 

homeassistant/components/utility_meter/sensor.py

@@ -688,7 +688,7 @@ class UtilityMeterSensor(RestoreSensor):
         self._collecting = None
 
     @property
-    def device_class(self):
+    def device_class(self) -> SensorDeviceClass | None:
         """Return the device class of the sensor."""
         if self._input_device_class is not None:
             return self._input_device_class

pylint/plugins/hass_enforce_type_hints.py

@@ -2508,6 +2508,7 @@ _INHERITANCE_MATCH: dict[str, list[ClassTypeHintMatch]] = {
                 TypeHintMatch(
                     function_name="device_class",
                     return_type=["SensorDeviceClass", None],
+                    mandatory=True,
                 ),
                 TypeHintMatch(
                     function_name="state_class",